/* Program: Determination of the duty point of stable centrifugal blowers
Author: OkothRonald */
#include <stdio.h>
#include<iostream>
#include<math.h>
#include<stdlib.h>
using namespace std; //permits inputting and outputting of data
int main()
{
//Defining the variables
int N;
float D,b,L,W,B2,g,U2,a2,Vr2,Vtheta2,Delta_h,Q;
//Initializing the variables
D=8.5/12;
b=5/12;
L=5/12;
W=6/12;
g=32.2;
N=750;
cout<<"Input the blade angle in degrees: ";
cin>>B2;
if(B2>0&&B2<90)
{
U2=M_PI*D*N;
a2=asin((L*W)/(M_PI*D*b));
Vr2=U2/((1/(tan((B2*M_PI)/180)))+(1/tan(a2)));
Vtheta2=Vr2*(1/tan(a2));
Delta_h=(3/208)*((U2*Vtheta2)/g);
Q=Vr2*M_PI*D*b;
cout << "\n\nDuty point for the input angle is: \n\n" ;
cout << "\t(i)Flow rate Q is " << Q;
cout<<"\n\t(ii)Static pressure change across the blade is "<<Delta_h;
}
else {
cout<<"Blade angle error\n"; }
return 0;}